The
recent findings by the US Geological Survey reveal some hotspots of persistent
organic pollutants in some parts of Mekong basin. This is a significant threat
to residents’ heath and wildlife in the area.

After
testing 531 animal samples collected from 450 wetlands across 5 Southeast Asian
countries, the research team found that fauna samples collected from some
hotspot sites such as Tonle Sap have high chemical
concentration.

The
research team also analyzed the concentration and distribution of
endosulfan, a persistent organic pollutant that has been banned in the
U.S. and some other countries. The study indicates that the total loading of
persistent organic pollutants in wetland sediment located in Mekong basin is
generally low; however, there are some hotspot sites where concentrations
exceeded established ecological risk thresholds.

“The
study findings provide important database for guiding development and conducting
preservation in Mekong basin in the future. Accordingly, future tasks focus on
the classification and distribution of wetlands in Mekong basin, investigation
into heavy metal contamination and monitoring of surface elevation in the
coastline of Southeast Asia”, said Scott Wilson of the USGS National Wetlands
Research Center.